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排序方式: 共有533条查询结果,搜索用时 15 毫秒
91.
Masatsugu Niwayama Hideaki Murata Shingo Sone Shigenobu Shinohara 《IEEJ Transactions on Electrical and Electronic Engineering》2007,2(4):485-487
We examined the influence of probe‐tissue distance on the relationship between the deep tissue absorption coefficient and the spatial profile of light intensity by Monte Carlo simulation and in vivo experiments, using noncontact spatially resolved near‐infrared spectroscopy (SRS). These results suggest that noncontact SRS can be reliably used for noncontact measurement of the absorption coefficient and oxygen saturation of deep tissues. © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
92.
固体滴定法是研究固溶量的一种新方法。本实验选择Mn-Al2O3色料,给其中加入Cr2O3,通过测定反射光谱f(R)、晶格常数、电子自旋共振(ESR),并计算晶格常数,分别得到加入Cr2O3前后的Mn-Al2O3的反射光谱与晶格常数的变化,依据该数据来推定着色离子Mn的固溶量及化学状态。为研究Mn-Al2O3红色料中Mn的固溶量,给其中加入Cr2O3,它使Mn-Al2O3红的色调发生变化,在此过程中发生如下反应:Cr^3 Mn^3 →Cr^4 Mn^2 ,Mn-Al2O3红色料在反射光谱520nm处有吸收峰值,给其中添加Cr2O3后峰值减小,用Cr^3 的固溶量(即Cr2O3的添加量)和峰值Δf(R)作图并延伸图线至Δf(R)=0点,此点对应的Cr2O3值即为Mn^3 的固溶量(Mn2O3的浓度)。实验证明,利用固体滴定法在一定精度范围内测定发色元素的固溶量取得一定程度成功。锰红色料中的发色离子状态为Mn^3 ,添加Cr2O3后,Cr能置换Mn-Al2O3中的Mn。铬是以Cr^3 化学状态固溶到Al2O3中的。 相似文献
93.
Xiaofei Dang Bei Zhang Chen Li Shingo Nagawa 《International journal of molecular sciences》2022,23(21)
Secondary cell wall thickening plays a crucial role in plant growth and development. Diploid woodland strawberry (Fragaria vesca) is an excellent model for studying fruit development, but its molecular control of secondary wall thickening is largely unknown. Previous studies have shown that Arabidopsis NAC secondary wall thickening promoting factor1 (AtNST1) and related proteins are master regulators of xylem fiber cell differentiation in multiple plant species. In this study, a NST1-like gene, FvNST1b, was isolated and characterized from strawberry. Sequence alignment and phylogenetic analysis showed that the FvNST1b protein contains a highly conserved NAC domain, and it belongs to the same family as AtNST1. Overexpression of FvNST1b in wild-type Arabidopsis caused extreme dwarfism, induced ectopic thickening of secondary walls in various tissues, and upregulated the expression of genes related to secondary cell wall synthesis. In addition, transient overexpression of FvNST1b in wild-type Fragaria vesca fruit produced cells resembling tracheary elements. These results suggest that FvNST1b positively regulates secondary cell wall formation as orthologous genes from other species. 相似文献
94.
Arne Knudsen Hiroshi Makino Kengo Morioka Hidekazu Otomaru Hiroshi Matsumoto Shingo Satoh Andrew Thom Gordon Munns Joyce Yamamoto Markus Reiterer 《International Journal of Applied Ceramic Technology》2019,16(1):324-334
A new Pt-Al2O3 multilayer composite system has been developed and validated with an Accelerated Life Test (ALT) to confirm its potential for long-term use in implantable medical devices (IMD). Panels containing over 100 Pt vias were subjected to highly accelerated immersion testing in deionized water at temperatures ranging from 90 to 175°C. Deionized water was employed as it best represents the IMD use environment. Degradation of individual Pt vias was evaluated using fluorescent dye infiltration into the subsurface of the panels. ALT guided refinement of materials and processing to produce a Pt-Al2O3 multilayer composite system with promising performance for possible use in implantable devices. 相似文献
95.
Lu Deng Shingo Urata Yasuyuki Takimoto Tatsuya Miyajima Seung Ho Hahn Adri C. T. van Duin Jincheng Du 《Journal of the American Ceramic Society》2020,103(3):1600-1614
Atomistic computer simulations can provide insights into silicate glass-environment interactions with the recent development of reactive potentials. However, the accuracy of generated glass structures with these potential was usually not fully examined. In this paper, the capability of the reactive force field (ReaxFF) to describe the short and medium range structure features of sodium silicate glasses in molecular dynamics simulations is investigated by comparing a widely used partial charge pairwise potential and available experimental data. Glass structure information such as pair distribution function (PDF), coordination number, Qn species, neutron broadened structure factor, and X-ray broadened structure factor of the glass structures from ReaxFF simulations were calculated and compared to evaluate the generated glass structure. Advantages and limitations of the potentials and glass forming procedures, as well as areas of further improvement, were discussed. The results show that the recently refined ReaxFF parameters through the proposed procedure enable the simulations of sodium silicate glass structures with minimal defects, which paves the way to investigate water-glass interaction mechanisms with the reactive enabled potentials. 相似文献
96.
Shingo Kanemura Motonori Matsusaki Kenji Inaba Masaki Okumura 《International journal of molecular sciences》2020,21(24)
Complicated and sophisticated protein homeostasis (proteostasis) networks in the endoplasmic reticulum (ER), comprising disulfide catalysts, molecular chaperones, and their regulators, help to maintain cell viability. Newly synthesized proteins inserted into the ER need to fold and assemble into unique native structures to fulfill their physiological functions, and this is assisted by protein disulfide isomerase (PDI) family. Herein, we focus on recent advances in understanding the detailed mechanisms of PDI family members as guides for client folding and assembly to ensure the efficient production of secretory proteins. 相似文献
97.
Yuriko Okazaki Shinichiro Okazaki Shingo Asamoto Pang‐jo Chun 《Computer-Aided Civil and Infrastructure Engineering》2020,35(8):775-792
The growing demand for a more efficient maintenance of concrete bridges requires a model that tracks the deterioration of each bridge based on inspection data. Although it has been expected that machine learning could be applied to this problem, inspection data sparsely distributed over time are not suitable for machine learning in contrast to the continuous big data usually targeted. This study applies machine learning to a regression model of crack formation and propagation using inspection data to confirm the applicability. It includes the selection of the optimal algorithm, development of the model based on a novel methodology, and factor analysis using the model. Accordingly, the model was constructed by Gaussian process regression and it could appropriately extract the differences in the progress of crack damage due to multiple influential factors. The results demonstrate the excellent applicability of machine learning even to sparse data. 相似文献
98.
In this study on a novel glass-ceramic containing hexagonal CaAl2Si2O8 crystals embedded in a SiO2–Al2O3–CaO glass, we used molecular dynamics simulations to unravel the toughening mechanism of the partially crystallized composite material. The crystalline phase is composed of alternate layers of SiO4/AlO4 tetrahedra and calcium ions. After careful modeling of crystals embedded in the glass matrix, we conducted crack propagation simulations using single-notched models. We found that: (a) when a crack propagates parallel to the cleavable calcium layer, the glass-ceramic breaks in a brittle way since the crack passes through the fragile interlayer promptly, (b) the stiffer SiO4/AlO4 oxide layer can inhibit crack propagation, and the crack is thus deflected to the interface between the crystal and the glass matrix; and (c) a calcium layer present between the glass matrix and the edge of the CaAl2Si2O8 crystal is more fragile than those inside the crystal, indicating that cracks prefer to travel along the glass-crystal interface. These theoretical simulations successfully demonstrated that the anisotropy and the fragile feature of the crystals lead to microcrack toughening of the glass-ceramic. In addition, we discuss deformation anisotropy in the microscale by constructing a larger model that includes randomly orientated multiple CaAl2Si2O8 crystals. 相似文献
99.
Hisayoshi Mitamura Seiichiro Matsumoto Takashi Miyazaki Timothy J. White Kiyoshi Nukaga Yoshihiro Togashi Tamio Sagawa Shingo Tashiro Desmond M. Levins Akira Kikuchi 《Journal of the American Ceramic Society》1990,73(11):3433-3441
The polyphase titanate ceramic containing sodium-rich simulated high-level nuclear waste was doped with 0.69 wt% of 244 Cm to accelerate long-term self-irradiation due to α decays. α autoradiography showed that α emissions were almost uniformaly distributed throughout the curium-doped samples on a >20-μm scale although micropore surfaces and titanium oxide agglomerates were free of α-emitting nuclides. The phase assemblage of the curium-doped titanate ceramic included freudenbergite and loveringite in addition to the more abundant oxide phases: hollandite, perovskite, and zirconolite. Accumulation of α decays was accompanied by a gradual decrease in density. The increment of density was – 1% after an equivalent age of 5000 yr. Leach tests showed a slight trend toward higher total release of curium with equivalent age. The release of soluble nonradioactive elements (e.g., Na, Cs, Sr, and Ca) in the oldest specimens (equivalent age, 2000 yr) varied from specimen to specimen but, on average, were higher than specimens that had suffered a lower radiation dose. 相似文献
100.
Fabrication of Bi2Sr2CaCu2Ox films on metal substrates by the chemical process using metal alkoxides
The formation behaviour of Bi2Sr2CaCu2Ox from compounds prepared by hydrolysis of metal alkoxides was studied and Bi2Sr2CaCu2Ox films on metal substrates were fabricated using a metal alkoxide solution. Bi2Sr2CaCu2Ox was formed through intermediate phases such as Bi2Sr2Cu1Ox, Bi2CuO4, SrCO3, CaCO3 and CuO. Bi2CuO4 was initially formed with SrCO3, CaCO3 and CuO, and then reacted with SrCO3 to form Bi2Sr2Cu1Ox. Bi2Sr2Cu1Ox reacted with CaCO3 and CuO to give Bi2Sr2CaCu2Ox. Bi2Sr2CaCu2Ox films were successfully fabricated on nickel substrates using the metal alkoxide solution at the nominal composition of BiSrCaCu=2223. Bi2Sr2CaCu2Ox was precipitated on Ni substrates at firing temperature of 770 °C or above, and a sharp T
c was obtained at the firing temperature of 800 °C. 相似文献